Automatic drop door mechanism



May 6, 1952 G. D. FRAUNFELDER 2,595,836

AUTOMATIC DROP DOOR IIEOIIANISII Filed June 27, 1946 4 Sheets-Sheet 1 INVENTOR IZ-P @@.Weewl ATTORNEYV GEoRGs D. FRAUMFELDER,

May 6, 1952 G. D. FRAUNFELDz-:R

AUTOMATIC DROP DOOR MECHANISM 4 Sheets-Sheet 2 Filed June 27, 1946 WVENTOR GEORGE D. Fbi/mmFame- QI A, ATTORNEY May 6, 1952 G. D. FRAUNFELDER AUTOMATIC DROP DOOR MECHANISM 4 Sheets-Sheet 3 Filed June 27, 1946 INvENToR GeoRGe D. FRAUNFELDER,

ATTORNEY May 6, 1952 G. D. FRAUNFELDER AUTOMATIC DROP DOOR MECHANISM 4 Sheets-Sheet 4 Filed June 27, 1946 lNVaNToR GEORGE D. FRAUNFELDER ATTORNEY Patented May 6, 195'2 AUTOMATIC DROP DOOR MECHANISM George D. Fraunfelder, Easton, Pa., assignor to Easton Car & Construction Company, Easton, Pa., a corporation of Pennsylvania Application June 27, 1946, Serial No. 679,735

(Cl. 10S-274) 2 Claims.

1 4 c The invention relates generally to body structures adapted for use on dump vehicles designed to be drawn or to travel over railways or roadbeds, and it primarily seeks to provide novel dump body structure including a dump door and novel door actuating mechanism effective to automatically open or lower the dump door as the body is dumped, and to lift or return said door to its closed position as the body is returned to its normal or lowered position.

An object of the invention is to provide novel door actuating mechanism of the character stated which is fast acting and capable of accomplishing its door opening or closing function, that is the moving of the door from its closed position to the open position in which it is in a common plane with the body floor, or from saidv co-planar position to the closed position, during a limited amount of movement of the body in the dumping or return or righting direction.

Another object of the invention is to provide a novel door actuating mechanism of the character stated which is devoid of single shear `pivotal connections likely to shear and disrupt the whole mechanism, and in which the parts are so constructed and cooperatively arranged that the forces incidental to door actuation are confined to a transverse center line at each end of the body with the bearings and supports for the various parts balanced on said center lines, thereby to apply said forces equally to said bearings and cooperating structures and provide great strength and also for the equal wearing of parts.

Another object of the invention is to provide novel door actuating mechanism of the character stated in which there is included a self locking feature making it impossible to open the dump door while the b ody is in its normal, lowered position.

Another object of the invention is to provide novel door actuating mechanism of the character stated in which a set of door actuating devices is completely housed in each end of the dump body in a manner for being hidden and inaccessible when the body is in its normal, lowered position, and in which only a single element of each said set projects in connection with the door and from an aperture in the respective body end when the body is in the dumping position.

Another object of the invention is to provideY novel door actuating mechanism of the character stated in which each set of door actuating devices includes a threadably mounted element subject to adjustment for determining the proper cooperative relation of the door and the body.

Another object of the invention is to provide novel door actuating mechanism of the character stated in which each set of door actuating devices includes a triangular rocker member presenting three pivot centers one of which has fixed bearing on the body, a second one of which is connected to one end of an actuator link having its other end pivotally connected with the door, and the third of which is connected to a compression column composed of two telescoping sections one connected to the rocker member and the other to a fixed bearing on the chassis which supports the dump body.

Another object of the invention is to provide novel door actuating mechanism of the character stated in which the rocker member is bifurcated to receive the pivotal connection with the compression column and the actuator link is bifurcated to receive the rocker member, thereby to place said rocker member, said compression column and said actuator link in a common plane.

Another object of the invention is to provide novel door actuating mechanism of the character stated in which the parts are so constructed and cooperatively arranged that the two pivotal connections of each actuator link, namely one with the door andthe other with the rocker member, and the pivotal connection of the rocker member with the compression column lie substantially in line when the door is closed, thereby providing a toggle lock preventing inadvertent opening 4 of the door.

With the above and other objects in view that will hereinafter appear, the nature of the invention will be more clearly understood by following the description, the appended claims, and

the several views illustrated in the accompanying drawings.

In the drawings:

Figure 1 is a fragmentary side elevation illustrating one end portion of a vehicle embodying the invention.

Figure 2 is an end elevation of the vehicle shown in Figure 1, the dump body being shown in its normal, lowered position in full lines and in the fully tilted or dumping position in dotted lines.

Figure 3 is a fragmentary vertical cross section taken on the line 3-3 of Figure 2.

Figure 4 is a fragmentary vertical cross section showing the dump body in the process of being tilted or dumped, the parts being in the position at which the body floor and the door have just reached the co-planar relation, an additionally 3 tilted position also being indicated in dotted lines.

Figure 5 is a fragmentary horizontal sectional view taken on the line 5 5 on Figure 2.

Figure 6 is a detail perspective view of one of the actuater links.

Figure 7 is a detail perspective View of one of the rocker members.

Figure 8 is a detail perspective View of one of the compression columns.

Figure 9 is a fragmentary vertical cross section taken on the line 9-9 on Figure 2.

In the example of embodimentof the invention herein disclosed, there is included a chassis generally designated 5 and which is supported on wheels 6. It is to be understood that the wheels may be equipped with pneumatic tires for travel over highways, or they may be flanged wheels capable of running on rails.

The chassis 5 includes two outer or main longitudinal III-beams 'I and two inner longitudinal channel beams 8. The beams 'I at the single side of the Vehicle or trailer over which dumping is to be accomplished has a plurality of hinge bearings 9 xed thereto at intervals therealong to receive the hinge pintles II! by which the hinge bearings II of the dump body generally designated I2 are pivoted.

The body I2 has a bottom structure composed of a multiple of cross beams I3 upon which lis mounted a iioor plate I4, and spaced above the plate I4 is a main floor plate I5, suitable planking being interposed between the floor plates in the manner illustrated in Figure 3.

A longitudinal channel beam I6 is mounted along the dump side of the body floor structure, and a plurality of door hinge bearings I1 are secured in longitudinally spaced relation on said beam. Outwardly and downwardly curved shed plates I8 extend from the main floor plate IB in concentric relation to the bearing centers in the manner clearly illustrated in Figures 2 and 4 of thebdrawings.

The body I2 includes xed end structures, each hollow, formed of parallel spaced plates I9, interposed spacer channels 20, side plates 2I and a top plate 22, the latter preferably inverted V- shaped. A rigidly mounted door 23 is provided along the non-dumping side of the body. A dump door, suitably pivoted, is provided at the yopposite or dumping side of the body.

The dump door has an inner plate 24 which, when dumping, is disposed on the same plane with the main body floor I 5 in the manner illustrated in Figures 2 ande. The dump door also includes a longitudinal base channel beam 25 to which hinge brackets 26 are secured, each said bracket having a foot 21 disposed to bear against the beam I6 while the body is in the process of dumping.V The dump door also includes a longitudinal top channel beam 28, a plurality of reinforcing uprights or transverse beams 25 disposed in spaced relation intermediately of the ends of the door, and a top angle plate 30. At each end of the dump door, a thick plate 3l is welded to the fabricated door and is extended downwardly and provided with an abutment foot 32 for engaging the beam I6, and a bearing 33 for hinge connection with the adjacent beam supported bracket. Each end plate 3I also is provided intermediately of its ends with an inwardly projected ear extension which is disposed to eX- tend into the hollow interior of the respective dump body end when the dump door is closed in the manner illustrated in Figures 2 and 5. Each .4 of the ear extensions 34 is attached to a set of door operating mechanism in the manner clearly illustrated in Figures 2, 3, 4 and 5.

In position for projecting into the hollow oi" each of the dump body ends a bearing 35 is supported across the inner chassis beams 8, and to each bearing 35 a compression column is pivoted as at 36. One of the compression columns is illustrated in detail in Figure 8, and each said column comprises a plunger 31 having an eye at its lower end and forming the pivotal connection, and each plunger is telescoped in a sleeve SS having a bifurcated upper end. Each sleeve provides end abutment 40 for engagement with the telescoped end extremity 4I of the respective plunger 31.

The bifurcated end of each compression column is pivoted as at 42 to one corner of a triangular rocker member 43 having another of its three corners pivoted as at 44 in a bearing secured between the side plates of the respective dump body end structure. A reinforcing gusset 45 may be provided beneath each said bearing. The third corner of each rocker member 43 is pivoted as at 4B to a bearing in the open end il of an actuating link generally designated 48. A guide channel 49 is welded or otherwise secured along one edge of the rocker member in the manner best illustrated in Figures '-7 and 9 of the drawings in position for entering the opening in the end of the actuator link during relative movement of the parts in a Amanner for preventing obstructive contact or jamming of said parts.

The actuator link structure is best illustrated in Figure 6 of the drawings and it will be observed that each said link includes a nut end portion 50 for vthreadably receiving the rod eX- tension 5! which is pivotally connected at 52 to the respective ear extension 34 of the dump door. The extension ears 34 and the connected rod eX- tensions `5I operate through openings 53 in the end structure plating opposed to the inner face of the dump door in the manner clearly illustrated in Figure 4, and the links operate through suitable openings 54 provided in one of the spacer channels 20.

While any suitable means may be employed for lifting the dump body from the lowered position illustrated in Figures 1 and 2 to the dumping position illustrated in dot and dash lines in Figure 2, it is preferred that the body be provided with a hoist lift connection 55 which may be engaged* by a hoist lift at the point of dumping for tilting the body about its dumping pivot.

It will be apparent by reference to Figure 2 of the drawing that as the dump body is swung upwardly about its pivotal mounting on the chassis the dump door will be opened very rapidly, attaining the co-planar relation to the dump body bottom as the body reaches the thirty degree angle. The compression columns will function as solid columns until the body reaches the full line position illustrated in Figure 4, and thereafter the sleeves 38 will move outwardly on the plungers in the manner illustrated in dotted lines in Figure 2. The resulting rocking of the rocker members 43 causes the actuater links shown in detail in Figure 6 to force the dump door outwardly in the manner stated, and as the body is again lowered the reverse movement of the rocker members draws the actuater links inwardly to reverse the process and rapidly draw the dump door to the closed position illustrated in full lines in Figure 2.

It is to be noted that when the dump body is in the lowered position illustrated in full lines in Figure 2, the pivotal connection of each actuater link with the dump door, the pivotal connection of said link with the rocker member 43, and the pivotal connection of said rocker member with the compression column will all lie in line, thereby providing a toggle lock.

It will be apparent from the foregoing that' the door operating mechanism herein disclosed is rapid in operation and presents the dump door in co-planar relation with the floor of the dump body at not more than thirty degrees of movement of the body floor. The door operating mechanism is substantially fool-proof and is devoid of any single shear pivot connections. It will be apparent by reference to Figures 3 and 5 of the drawings that all pivot points are arranged in double shear relation with substantial bearings provided for all pivot pins. The door operating mechanisms are so constructed and arranged that they are housed within the hollow ends of the dump body and only the extreme ends of the actuater links project from said ends when the door is open, thereby providing minimum opportunity for contact and breakage of said mechanisms.

It will also be apparent by reference to Figures 3 and 5 of the drawings that all parts of the door operating mechanisms are centered in a single transverse plane, thereby to conne all forces to the transverse center line on which said parts are mounted. Thus the forces are presented equally to all of the bearings and related structure, and equal wear is to be expected at all points.

The construction and arrangement of the compression columns 31, 38 is important. These columns function under compression as a single rigid unit up to the point where the dump door becomes ilush with the bottom lof the dump body, and beyond this point the sleeve moves outwardly on the plunger with the body in the manner previously described. On the xreverse or lowering movement ofthe body the sleeves slide downwardly on the plungers until they come to rest on the end extremities of said plungers, and thereafter the dump door is automatically and rapidly raised in the manner previously described.

While one form of the novel door operating mechanism is herein disclosed, it is to be understood that various changes and modifications in the specic form of the parts may be made without departing from the spirit of the invention as defined in the following claims.

I claim:

ll. In a dump vehicle, a chassis, a dump body tiltably mounted on said chassis and including a floor, a side wall and two end walls forming a part of and movable with the dump body and dening between them a lading receiving space in said body, and a door swingably mounted at its lower edge portion on the body and over which lading from the body is dumped, and at least one set of door operating devi-ces having connections with the door, the body and the chassis, said door operating device set being mounted wholly above the chassis and so constructed and arranged as to automatically open the door as the body is dumped and close the door as the body is returned to its normal position and comprising a triangular rocker member presenting first, second and third pivot centers the first of which has fixed pivotal bearing on the body, the second one of which is pivotally connected to one end of an actuater tension link having its other end pivotally connected with the door, and the third of which is pivotally connected to a compression column composed of two telescoping sections one pivotally connected to the rocker member as aforesaid and the other of which is pivotally connected to a xed bearing on the chassis. said five pivotal connections of the door operating devices being cooperatively arranged to cause said door to be moved into coplanar relation with the floor prior to completion of the dump tilt incidental to each body dumping operation, and said telescoping sections serving to permit elongation of the compression column during each dumping operation after the door and floor have attained said co-planar relation. said link being bifurcated so that it can receive the rocker member and its pivotal connection with the compression column in its bifurcation, and said iive pivotal connections of the door operating devices also being cooperatively arranged to cause the two pivotal connections of the link and said rocker member and compression column pivotal connection to be arranged in door locking alignment and in said bifurcation when the door is closed.

2. In a dump vehicle, a chassis, a dump body tiltably mounted on said chassis and including a floor, a side wall and two end walls forming a part of and movable with the dump body and defining between them a lading receiving space in said body, and a door swingably mounted at its lower edge portion on the body and over which lading from the body is dumped, and at least one set of door operating devices having connections with the door, the body and the chassis, said door operating device set being mounted wholly above the chassis and so constructed and arranged as to automatically open the door as the body is dumped and close the door as the body is returned to its normal position and comprising a triangular rocker member presenting first, second and third pivot centers the first of which has fixed pivotal bearing on the body, the second one of which is pivotally connected to one end of an actuater tension link having its other end pivotally connected with the door, and the third of which is pivotally connected to a compression column composed of two telescoping sections one pivotally connected to the rocker member as aforesaid and the other of which is pivotally connected to a fixed bearing on the chassis, said five pivotal connections of the door operating devices being cooperatively arranged to cause said door to be moved into co-planar relation with the floor prior to completion of the dump tilt incidental to each body dumping operation, and said telescoping sections serving to permit elongation of the compression column during each dumping operation after the door and oor have attained said co-planar relation, said link being bifurcated so that it can receive the rocker member and its pivotal connection with the compression column in its bifurcation, and said five pivotal connections of the door operating devices also being cooperatively arranged to cause the two pivotal connections of the link and said rocker member and compression column pivotal connection to be arranged in door locking alignment and in said bifurcation when the door is closed, and said rocker member having guide flanges thereon receivable in said link bifurcation to guide the rocker member into the bifurcation as the door moves to its closed position.

GEORGE D. FRAUNFELDER.

(References on following page) 7 REFERENCES CITED Number The following references are of record in the 1'749530 le of this patent: UNITED STATES PATENTS 5 3211406 Number Name Date 1,333,293 Clark et a1 Mar. 9, 1920 1,468,350 Hale et a1 Sept. 18, 1923 Number 1,563,830 Brown Dec. 1, 1925 137,069

Name Date Flowers Mar. 4, 1930 Flowers Aug. 8, 1933 Burner Nov. 21, 1933 Merchant June 8, 1943 FOREIGN PATENTS Country Date Switzerland Feb. 17, 1930 

